Verification of Core-Fuel Inventory of a Fast Critical Facility by Monitoring Reactor Physics Parameters

摘要

On the safeguards problem, technical feasibility was studied for experimentally verifying core-fuel inventory of a fast critical facility. The FCA Assembly VIII-1 with plutonium-fueled test zone was used for this purpose. Six loading patterns were chosen in the verification experiment to simulate the diversion of Pu-fuel from the core. The Pu-fuel removed from the core was about 3.5 -- 5.8 kg. Verification techniques are based on the monitoring of small changes in fission rates and beta /l caused by the diversion of some amount of Pu-fuel. The fission rates were measured by a fission chamber technique with a hundred exp 239 Pu fission chambers located in the core region and multi-chamber scanning electronics, while beta /l values were measured by power noise analysis with two herium-3 chambers. The verification experiment indicates that the fission rates and beta /l monitor well follow the quantities of plutonium removed from the core. It is concluded that the verification of core-fuel inventory is feasible by using the present monitoring method. (Atomindex citation 14:800170)